Leases - Additional Information (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Statements [Line Items]
Expense relating to short-term leases for which recognition exemption has been used	₩ 152,644	₩ 172,711
Expense relating to leases of low-value assets for which recognition exemption has been used	3,121	4,659
Cash outflow related to leases	863,651	901,041
Discounted unguaranteed residual value of assets	₩ 31,857	₩ 25,521
Maximum
Statements [Line Items]
Implicit interest rate on finance lease	17.15%	17.03%
Minimum
Statements [Line Items]
Implicit interest rate on finance lease	0.00%	0.00%
Power Purchase Agreement \| Maximum
Statements [Line Items]
Lease term of finance lease	11 years
Power Purchase Agreement \| Minimum
Statements [Line Items]
Lease term of finance lease	2 years
Jordan Electric Power Company \| Power Purchase Agreement
Statements [Line Items]
Lease term of finance lease	25 years
Fujeij Wind Power Plant \| Power Purchase Agreement
Statements [Line Items]
Lease term of finance lease	20 years
Federal Electricity Commission \| Power Purchase Agreement
Statements [Line Items]
Lease term of finance lease	25 years

The cash outflow for leases.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 53
-Subparagraph g
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_g&doctype=Standard
-URIDate 2024-03-27

+ Details

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Period Type:	duration

- Definition

The amount of the discounted unguaranteed residual value of assets subject to finance leases. Unguaranteed residual value is the portion of the residual value of the underlying asset, the realisation of which by a lessor is not assured or is guaranteed solely by a party related to the lessor. Finance lease is a lease that transfers substantially all the risks and rewards incidental to ownership of an underlying asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 94
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_94&doctype=Standard
-URIDate 2024-03-27

+ Details

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Period Type:	instant

- Definition

The amount of the expense relating to leases of low-value assets accounted for applying paragraph 6 of IFRS 16. This expense shall not include the expense relating to short-term leases of low-value assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 53
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_d&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of the expense relating to short-term leases accounted for applying paragraph 6 of IFRS 16. This expense need not include the expense relating to leases with a lease term of one month or less. Short-term lease is a lease that, at the commencement date, has a lease term of 12 months or less. A lease that contains a purchase option is not a short-term lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2024-01-01
-Paragraph 53
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2024-en-r&anchor=para_53_c&doctype=Standard
-URIDate 2024-03-27

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- Definition

implicit interest rate on finance lease.

+ References

No definition available.

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- Definition

Lease term of finance lease.

+ References

No definition available.

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- Definition

Statements.

+ References

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